aggregator

Documentation

Index

• Variables
• func NewInconsistentMergeError(a1, a2 export.Aggregator) error
• func RangeTest(number metric.Number, descriptor *metric.Descriptor) error
• type Buckets
• type Count
• type Distribution
• type Histogram
• type LastValue
• type Max
• type Min
• type MinMaxSumCount
• type Points
• type Quantile
• type Sum

Variables

var (
	ErrInvalidQuantile  = fmt.Errorf("the requested quantile is out of range")
	ErrNegativeInput    = fmt.Errorf("negative value is out of range for this instrument")
	ErrNaNInput         = fmt.Errorf("NaN value is an invalid input")
	ErrInconsistentType = fmt.Errorf("inconsistent aggregator types")

	// ErrNoData is returned when (due to a race with collection)
	// the Aggregator is check-pointed before the first value is set.
	// The aggregator should simply be skipped in this case.
	ErrNoData = fmt.Errorf("no data collected by this aggregator")
)

Functions

func NewInconsistentMergeError

func NewInconsistentMergeError(a1, a2 export.Aggregator) error

NewInconsistentMergeError formats an error describing an attempt to merge different-type aggregators. The result can be unwrapped as an ErrInconsistentType.

func RangeTest

func RangeTest(number metric.Number, descriptor *metric.Descriptor) error

RangeTest is a commmon routine for testing for valid input values. This rejects NaN values. This rejects negative values when the metric instrument does not support negative values, including monotonic counter metrics and absolute measure metrics.

Types

type Buckets

type Buckets struct {
	Boundaries []metric.Number
	Counts     []metric.Number
}

Buckets represents histogram buckets boundaries and counts.

For a Histogram with N defined boundaries, e.g, [x, y, z]. There are N+1 counts: [-inf, x), [x, y), [y, z), [z, +inf]

type Count

type Count interface {
	Count() (int64, error)
}

Sum returns the number of values that were aggregated.

type Distribution

type Distribution interface {
	MinMaxSumCount
	Quantile
}

Distribution supports the Min, Max, Sum, Count, and Quantile interfaces.

type Histogram

type Histogram interface {
	Sum
	Histogram() (Buckets, error)
}

Histogram returns the count of events in pre-determined buckets.

type LastValue

type LastValue interface {
	LastValue() (metric.Number, time.Time, error)
}

LastValue returns the latest value that was aggregated.

type Max

type Max interface {
	Max() (metric.Number, error)
}

Max returns the maximum value over the set of values that were aggregated.

type Min

type Min interface {
	Min() (metric.Number, error)
}

Min returns the minimum value over the set of values that were aggregated.

type MinMaxSumCount

type MinMaxSumCount interface {
	Min
	Max
	Sum
	Count
}

MinMaxSumCount supports the Min, Max, Sum, and Count interfaces.

type Points

type Points interface {
	Points() ([]metric.Number, error)
}

Points returns the raw set of values that were aggregated.

type Quantile

type Quantile interface {
	Quantile(float64) (metric.Number, error)
}

Quantile returns an exact or estimated quantile over the set of values that were aggregated.

type Sum

type Sum interface {
	Sum() (metric.Number, error)
}

Sum returns an aggregated sum.